North Korea is preparing to conduct its next nuclear test amid disturbance in South Korea. Pyongyang will reportedly conduct another test around the time of South Korea's presidential election, a high-profile North Korean defector has said.

The reclusive nation appears to be pursuing its nuclear programme despite growing international pressure, Yonhap news agency reported.

Thae Yong-ho, a former high ranking official at the North Korean embassy in London, said that the country's foreign ministry had sent documents to its overseas missions, requesting them to grant permission to carry out its sixth and seventh nuclear tests in the coming New Year.

"In particular, it calls for preparations as North Korea would seek to conduct a nuclear test around the presidential election," Thae said on Friday, 23 December, in a closed-door parliamentary intelligence committee session, according to lawmakers.

Pyongyang has conducted two nuclear tests in 2016 alone following those in 2006, 2009 and 2013.

North's supreme leader, Kim Jong-un, reportedly wants Pyongyang to be recognised as a nuclear state, like Pakistan or India, a status rejected by South Korea and the US.

"After being recognized as a nuclear state, North Korea hopes to resolve pending issues through international dialogue," Thae added.

Meanwhile, South Korea is expected to hold a presidential election in 2017 following the country's parliament approving a motion on 9 December to impeach President Park Geun-hye over a corruption scandal. The Constitutional Court has up to 180 days since the impeachment to review whether to unseat or reinstate her.

While Park's five-year term ends in February 2018, a new election has to be held in 60 days to pick a new president if the impeachment is upheld.

Commenting on the political situation in Seoul, Thae said North Korea hopes that the South may take a fresh approach towards Pyongyang under a new administration.

"Pyongyang hopes that doubts about the effectiveness of sanctions against North Korea gain traction in a short period of time. It wants South Korea to seek a new inter-Korean policy," he was quoted as saying by a South Korean lawmaker.